Try numerical: \( f(1) = (1 - 3)/(1 + 1) = -2/2 = -1 \), \( f(-1) = ((-1)^3 - 3(-1))/(1 + 1) = (-1 + 3)/2 = 1 \), so \( f(f(1)) = f(-1) = 1 = x \). So \( x = 1 \) is a solution. - go-checkin.com